Ioversol is disclosed as a useful nonionic X-ray contrast agent in U.S. Pat. No. 4,396,598 incorporated herein by reference. N,N'-bis(2,3-dihydroxypropyl)-5-[N(2-hydroxyethyl) glycolamido] -2,4,6-triiodoisophthalamide, more commonly called Ioversol has the following structure: ##STR1##
In the production of Ioversol, purification columns are used to remove impurities from the crude Ioversol product following completion of the synthetic steps as described in U.S. Pat. No. 4,396,598 and incorporated herein by reference. The costs and time involved in a purification operation, such as regenerating and replacing the purification columns is significant in the purification of Ioversol. Large amounts of costly resins and large volumes of solutions are also necessary to regenerate the purification columns between uses. These costs are significant in the production of Ioversol.
An improved procedure which eliminates the need for costly purification columns to remove low molecular weight impurities from the crude Ioversol product following synthesis thereof is desired as an alternative and/or a more cost efficient method of producing Ioversol. It is, therefore, an object of the present invention to meet these needs.